检索结果-南通市图书馆

Surface tuning of LaCoO_(3) perovskite by acid etching to enhance its catalytic performance

在线全文

学校读者我要写书评

暂无评论

Rare Metals 2021年第3期40卷 555-562页

作者： lu Dai Xin-bo lu Guo-Hai Chu Cheng-Huan He Wang-Cheng Zhan Guo-jun Zhou China Tobacco Zhejiang Industrial Co. LtdHangzhou 310024China Research Institute Catalysis School of Chemistry and Molecular EngineeringEast China University of Science and TechnologyShanghai 200237China

The stoichiometric LaCoO_(3) and nonstoichiometric LaCo_(1.2)O_(3) perovskite catalysts were prepared by citric acid sol-gel method,and then,LaCoO_(3) perovskite was etched with nitric *** structure,surface composition and reducibility of the catalyst were studied by X-ray diffraction(XRD),nitrogen desorption,transmission electron microscope(TEM),temperature program reduction of H_(2)(H_(2)-TPR) and X-ray photoelectron spectroscopy(XPS).It was found that nitric acid etching did not change the crystal structure and the overall morphology of the LaCoO_(3) catalyst,but it can cause the exposure of B-site Co metal to the surface of the *** a result,after acid etching,the reducibility of the LaCoO_(3) catalyst was improved,leading to the improvement in the catalytic activity of the LaCoO_(3) catalyst for CO oxidation and C_(3)H_(8) ***,the catalytic activity of the LaCoO_(3) catalyst after acid etching was higher than that of LaCo_(1.2)O_(3) and CoOx/LaCoO_(3) catalyst.

关键词： Perovskite oxide Acid etching CO oxidation Propane combustion

Synergistic effects of composition and heat treatment on microstructure and properties of vacuum die cast Al-Si-Mg-Mn alloys

在线全文

学校读者我要写书评

暂无评论

China Foundry 2018年第2期15卷 117-123页

作者： jun-jie Xu Ye Pan Tao lu Bing bo School of Materials Science and Engineering Southeast University Jiangsu Key Laboratory for Advanced Metallic Materials

The purpose of this study was to prepare high-quality Al-Si-Mg-Mn alloy with a good combination of strength and ductility employing the vacuum-assisted high-pressure die cast process. An orthogonal study of heat treatments was conducted to design an optimized T6 heat treatment process for both Al-10%Si-0.3%Mg-Mn and Al-11%Si-0.6%Mg-Mn alloys. The results demonstrate that no obvious blisters and warpage were observed in these two alloys with solid solution treatment. After the optimal T6 heat treatment of 530°C×3 h + 165°C×6 h, Al-11%Si-0.6%Mg-Mn alloy has better mechanical properties, of which tensile strength, yield strength and elongation reached 377.3 MPa, 307.8 MPa and 9%, respectively. The improvement of mechanical properties can be attributed to the high density of needle-like β″(Mg_5Si_6) precipitation after aging treatment and the fine and spherical eutectic Si particles uniformly distributed in the α-Al matrix.

关键词： heat treatment vacuum die casting Al-Si-Mg-Mn alloy microstructure mechanical properties

Controlling solid form and crystal habit of triphenylmethanol by antisolvent crystallization in a microfluidic device

在线全文

学校读者我要写书评

暂无评论

Chinese Chemical Letters 2024年第4期35卷 393-398页

作者： jun lu Jinrui Yan Yaohao Guo junjie Qiu Shuangliang Zhao bo Bao East China University of Science and Technology Shanghai 200237China Guangxi Key Laboratory of Petrochemical Resource Processing and Process Intensification Technology and School of Chemistry and Chemical Engineering Guangxi UniversityNanning 530004China

Crystal habit and crystal form are critical elements in determining product properties and functions. In this work, we developed a microfluidic antisolvent crystallization technique to rapidly screen and accurately control the solid form and crystal habit of triphenylmethanol(Ph_(3)COH). This advanced technique separates the primary mixing of solutions from crystal formation(nucleation and growth) by introducing the microfluidic device, avoiding clogging in microchannels to obtain high-quality crystals. The results show that we can achieve controllable preparation of pure 2Ph_(3)COH·DMSO(DMSO solvate), pure Ph_(3)COH(form β), and mixed crystals with different mass ratios. Moreover, the microscale can prompt the DMSO solvate to grow into hexagonal sheet-like and bulk crystals. We can regulate the aspect ratio of hexagonal sheet-like crystals in binary solvents and control the crystal habit of the form β to transition between long needle-like shapes and short hexagonal prisms in DMF-H_(2)O. Meanwhile, we revealed that the solvent ratio, the antisolvent flow rate, and the initial concentration of Ph_(3)COH are the main factors affecting the solid form selectivity and morphology transition. Such a novel method would be considered as a promising technique to be extended to screen and control key crystallization parameters of other substances.

关键词： Microfluidics Triphenylmethanol Antisolvent crystallization Crystal habit Solid form

MicroRNA-125b Accelerates and Promotes PML-RARa-driven Murine Acute Promyelocytic Leukemia

在线全文

学校读者我要写书评

暂无评论

Biomedical and Environmental Sciences 2022年第6期35卷 485-493页

作者： GUO bo QIN Ran CHEN Ji jun PAN Wen lu Xue Chun Department of Hematology The Second Medical Centre&National Clinical Research Center for Geriatric DiseasesChinese PLA General HospitalBeijing 100853China Department of Genetics Yale University School of MedicineNew HavenConnecticut 06510USA Yale Stem Cell Center Yale Cancer CenterNew HavenCT06520USA

Objective Most acute promyelocytic leukemia cases are characterized by the PML-RARa fusion oncogene and low white cell counts in peripheral *** Based on the frequent overexpression of miR-125-family miRNAs in acute promyelocytic leukemia,we examined the consequence of this phenomenon by using an inducible mouse model overexpressing human *** MiR-125b expression significantly accelerates PML-RARa-induced leukemogenesis,with the resultant induced leukemia being partially dependent on continued miR-125b ***,miR-125b expression led to low peripheral white cell counts to bone marrow blast percentage ratio,confirming the clinical observation in acute promyelocytic leukemia *** This study suggests that dysregulated miR-125b expression is actively involved in disease progression and pathophysiology of acute promyelocytic leukemia,indicating that targeting miR-125b may represent a new therapeutic option for acute promyelocytic leukemia.

关键词： miR-125b PML-RARA White blood cell bone marrow blast

Antiplatelet and myocardial protective effect of Shexiang Tongxin Dropping Pill in patients undergoing percutaneous coronary intervention:A randomized controlled trial

在线全文

学校读者我要写书评

暂无评论

Journal of Integrative Medicine 2022年第2期20卷 126-134页

作者： Yan-jun Lin Kun-li Jiao bo Liu lu Fang Shu Meng Department of Cardiology Xinhua HospitalShanghai Jiaotong University School of MedicineShanghai 200092China Haematopoiesis and Leukocyte Biology Laboratory Baker Heart and Diabetes Research InstituteMelbourneVIC 3004Australia

Background:High on-clopidogrel platelet reactivity could be partially explained by loss-of-function alleles of CYP2 C19,the enzyme that converts clopidogrel into its active *** Tongxin Dropping Pill(STDP)is a traditional Chinese medicine to treat angina *** has been shown to improve blood flow in patients with slow coronary flow and attenuate atherosclerosis in apolipoprotein E-deficient ***,whether STDP can affect platelet function remains ***:The purpose of this study is to examine the potential effects of STDP on platelet function in patients undergoing percutaneous coronary intervention(PCI)for unstable *** interaction between the effects of STDP with polymorphisms of CYP2 C19 was also ***,participants and intervention:This was a single-center,randomized controlled trial in patients undergoing elective PCI for unstable *** subjects were randomized to receive STDP(210 mg per day)plus dual antiplatelet therapy(DAPT)with clopidogrel and aspirin or DAPT *** outcome measures:The primary outcome was platelet function,reflected by adenosine diphosphate(ADP)-induced platelet aggregation and platelet microparticles(PMPs).The secondary outcomes were major adverse cardiovascular events(MACEs)including recurrent ischemia or myocardial infarction,repeat PCI and cardiac death;blood biomarkers for myocardial injury including creatine kinase-MB isoenzyme(CK-MB)and high-sensitive troponin I(hs Tn I);and biomarkers for inflammation including intercellular cell adhesion molecule-1(ICAM-1),vascular cell adhesion molecule-1(VCAM-1),monocyte chemoattractant protein-1(MCP-1)and ***:A total of 118 subjects(mean age:[66.8±8.9]years;male:59.8%)were included into analysis:58 in the control group and 60 in the STDP ***2 C19 genotype distribution was comparable between the 2 *** comparison to the control group,the STDP group had significantly lower CKMB(P<0.05)but similar hs Tn I(

关键词： Shexiang Tongxin Dropping Pill Traditional Chinese medicine Dual antiplatelet therapy CYP2C19 gene polymorphism Platelet reactivity

陈旧性骨质疏松性椎体压缩骨折骨不连的修复策略:一项病例分析

在线全文

学校读者我要写书评

暂无评论

中国组织工程研究 2025年第3期29卷 538-546页

作者：赵星丞王军陆明上海市公共卫生临床中心骨科上海市201508

背景:腰椎骨质疏松性压缩性骨折患者的脊柱和骨盆矢状位参数存在不同程度改变,将导致全脊柱/腰椎矢状面发生失平衡和再平衡。如果初次骨质疏松性椎体压缩骨折没有得到及时治疗,随着时间的推移将发展为陈旧性骨质疏松性椎体压缩骨折骨不... 详细信息

背景:腰椎骨质疏松性压缩性骨折患者的脊柱和骨盆矢状位参数存在不同程度改变,将导致全脊柱/腰椎矢状面发生失平衡和再平衡。如果初次骨质疏松性椎体压缩骨折没有得到及时治疗,随着时间的推移将发展为陈旧性骨质疏松性椎体压缩骨折骨不连。目的:观察陈旧性骨质疏松性腰椎体压缩骨折骨不连9例患者行经皮椎体成形(PVP)术后的修复效果。方法:回顾性分析2018年9月至2022年8月上海市公共卫生临床中心骨科收治的陈旧性老年骨质疏松性腰椎椎体压缩性骨折骨不连经皮椎体成形术后术椎再骨折患者9例的临床资料,所有患者均采用经皮椎体成形行再翻修治疗,同时规律进行抗骨质疏松治疗和康复训练。出院前及随访时复查患者的腰椎X射线平片及三维CT检测结果,评价骨水泥弥散情况,记录患者术前、术后、随访时的目测类比评分、腰椎Oswetry功能障碍指数(ODI评分)及Roussouly腰椎功能分型变化。结果与结论:①9例患者术后随访时均未发生神经损伤、感染、骨水泥椎管内渗漏、肺栓塞及过敏性休克等严重手术并发症,均未发生骨水泥相关的不良反应。有1例患者术后2年感染COVID-19致呼吸功能衰竭死亡。②术椎再骨折患者术后疼痛目测类比评分和ODI评分均显著低于翻修术前,末次随访经皮椎体成形翻修术后患者Roussouly腰椎功能分型显著改善;末次随访测量术椎椎体高度变化与术前比较无显著性意义。③上述结果提示,对陈旧性骨质疏松性腰椎体压缩骨折骨不连行经皮椎体成形治疗的患者而言,适量骨水泥注入和有效骨水泥弥散具有明显缓解术后疼痛作用,规律抗骨质疏松和术后有效康复训练有助于患者术后腰椎功能恢复。

关键词：骨质疏松经皮椎体成形骨水泥注入技术椎体成形术椎再骨折 Roussouly腰椎功能分型应力集中区

Targets capture by distributed active swarms via bio-inspired reinforcement learning

在线全文

学校读者我要写书评

暂无评论

Science China(Physics,Mechanics & Astronomy) 2025年第1期Mechanics & Astronomy) .卷 210-221页

作者： Kun Xu Yue Li jun Sun Shuyuan Du Xinpeng Di Yuguang Yang bo Li Institute of Biomechanics and Medical Engineering Applied Mechanics Laboratory Department of Engineering MechanicsTsinghua University Institute of Nuclear and New Energy Technology Tsinghua University Shanghai Aerospace Control Technology Institute Shanghai Key Laboratory of Aerospace Intelligent Control Technology College of Automation Engineering Nanjing University of Aeronautics and Astronautics

Natural swarms arranged from cells to herds are usually decentralized but display intriguing collective intelligence in coordinating individuals across large scales to efficiently achieve their common goals. Learning from nature may provide new strategies for controlling collective dynamics of synthetic swarms to accomplish specific functions. Here, we present a bioinspired computational framework that steers distributed active swarms to collectively capture and merge targets via reinforcement learning. We exploit collective milling structures of natural herds to cage the targets, and adopt a switching control policy inspired by sperms' chiral dynamics to optimize the trajectories of individuals, through which the active swarms can selforganize to enclose single or multiple distant targets in a dynamical, adaptive and scalable manner. There exists a critical swarm size, beyond which the excessive competition between agents would generate large mechanical forces, leading to capture instability but enabling the transition from short-distance to long-distance merging capture of multiple targets. This work provides physical insights into distributed active swarms and could offer a multilevel, decentralized strategy toward controlling swarm robotics in wide applications such as bio-medical devices, machine immunity, and target clearance.

关键词：

Effect of microstructure on short pulse duration shock initiation of TATB and initial response mechanism

在线全文

同方期刊数据库

学校读者我要写书评

暂无评论

Defence Technology（防务技术） 2020年第2期16卷 374-380页

作者： jun Wang Wei Cao Xiang-li Guo Bi-bo Cheng lu-lu Zhao Rui-rui Liu Xiao-wei Chen School of Mechatronical Engineering Beijing Institute of TechnologyBeijing100081China Institute of Chemical Materials China Academy of Engineering PhysicsNo.64Mianshan RoadMianyang CityChina

Micro-TATB particles with different sizes and 3D nanoporous TATB architectures with different specific surface areas were prepared through recrystallization to study short pulse duration shock initiation properties by electric gun *** micro-TATB,the initiation threshold significantly decreases with TATB average size ranging from 79.7μm to 0.5μ*** 3D nanoporous TATB architecture,the initiation threshold decreases and then increases with specific surface areas increased from 9.6 m^2/g to36.2 m^2/*** lowest initiation thresholds are obtained for the micro-TATB with average sizes of 1.3μm and 0.5μm,and 3D nanoporous TATB architecture with specific surface area of 22.4 m^2/*** shock initiation thresholds of micro-TATB and 3D nanoporous TATB architectures show significantly decreases with the porosity *** decomposition reaction and thermal conductivity properties were further investigated to understand the initial response *** porosity provides more collapse sites to generate high temperature for formation of hot *** low thermal conductivity and decomposition temperature could enhance the formation and ignition of the hot spots,and initial decomposition reaction of *** effect of the decomposition temperature is higher than that of the thermal conductivity on the shock initiation *** enhanced decomposition reaction could pro mote energy release and transfer process from the ignition to the combustio *** work offe rs a new insight to understand the effects of microstructure on the shock initiation properties and the initial response mechanism of TATB.

关键词： Short pulse duration shock initiation Microstructure TATB architecture Chemical reaction Initial response mechanism

Microstructural refinement and performance improvement of Cu-36 wt%Zn alloy by Al_(2)O_(3)nanoparticles coupling electromagnetic stirring

在线全文

学校读者我要写书评

暂无评论

Rare Metals 2022年第10期41卷 3560-3565页

作者： Ya-bo Fu Yi-Ping lu Zhi-jun Wang Zhi-Qiang Cao Ai-Jiao Xu School of Physics and Electronic Engineering Taizhou UniversityTaizhou318000China School of Materials Science and Engineering Dalian University of TechnologyDalian116024China School of Materials Science and Engineering Northwestern Polytechnical UniversityXi’an710048China

Cu-36 wt%Zn alloy is widely used in valves of water and heating and auto parts,***,the structure is still coarse,and performances are much *** structure and performances of Cu-36 wt%Zn alloy were investigated by adding Al_(2)O_(3)nanoparticles and *** indicate that by Al_(2)O_(3)nanoparticles coupling electromagnetic stirring,the Cu-36 wt%Zn alloy with refined microstructure was successfully *** average grain size is refined by 99%compared with that without nanoparticles and *** tensile strength(R_m)and percentage elongation after fracture(A11.3)increase by 20.58%and 19.40%,respectively,compared with that without nanoparticles and *** increase heterogeneous nucleation rate by 50%compared with that without *** depth of dezincification layer decreases by 78.71%compared with that without nanoparticles and stirring,as protective layer(Cu-Al_(2)O_(3)-Zn)is completely formed around the grain boundaries.

关键词： Microstructural refinement Rotating electromagnetic field Mechanical performance Al_(2)O_(3)nanoparticles